Aviation Investigation Report A13p0166
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AVIATION INVESTIGATION REPORT A13P0166 CONTROLLED FLIGHT INTO TERRAIN AIR NOOTKA LTD. DE HAVILLAND DHC-2 (FLOATPLANE) C-GPVB HESQUIAT LAKE, BRITISH COLUMBIA 3 NM W 16 AUGUST 2013 The Transportation Safety Board of Canada (TSB) investigated this occurrence for the purpose of advancing transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability. Aviation Investigation Report A13P0166 Controlled flight into terrain Air Nootka Ltd. de Havilland DHC-2 (floatplane) C-GPVB Hesquiat Lake, British Columbia 3 nm W 16 August 2013 Summary At 1015 Pacific Daylight Time, the de Havilland DHC-2 (Beaver) floatplane (registration C- GPVB, serial number 871), operated by Air Nootka Ltd., departed Hesquiat Lake, British Columbia, with the pilot and 5 passengers for Air Nootka Ltd.’s water aerodrome base near Gold River, British Columbia. Visibility at Hesquiat Lake was about 2 ½ nautical miles in rain, and the cloud ceiling was about 400 feet above lake and sea level. Approximately 3 nautical miles west of the lake, while over Hesquiat Peninsula, the aircraft struck a tree top at about 800 feet above sea level and crashed. Shortly after the aircraft came to rest, a post-crash fire developed. All 6 persons on board survived the impact, but the pilot and 1 passenger died shortly after. A brief 406 megahertz emergency locator transmitter signal was transmitted, and a search and rescue helicopter recovered the survivors at about 1600. Le présent rapport est également disponible en français. Aviation Investigation Report A13P0166 | 1 Factual information History of the flight The pilot arrived at Air Nootka Ltd.’s (Air Nootka) main base at about 0730,1 half an hour before any other employee. Air Nootka’s main base is located at the Gold River Water Aerodrome (CAU6), about 6 nautical miles (nm) south-southwest of Gold River, British Columbia. The pilot departed the base in C-GPVB at 0850 with passengers bound for Louie Lagoon, about 32 nm west of CAU6. This was the first Air Nootka flight of the day. After dropping off the passengers at Louie Lagoon, British Columbia, C-GPVB departed for Hesquiat Lake, British Columbia, 26 nm southeast of Louie Lagoon, to pick up 5 hikers waiting at a dock at the south end of the lake (Figure 1). Spot and Latitude waypoints in Figure 1 are derived from the pilot’s own SPOT© Satellite Messenger2 tracker and the aircraft’s Latitude3 tracking system. While flying over Nootka Sound, British Columbia, at just under 300 feet above sea level (asl), en route from Louie Lagoon to Hesquiat Lake, the pilot radioed Air Nootka’s base to report that the weather was good enough for 2 company aircraft to depart the company’s base for Hesquiat Lake to pick up 9 additional hikers at the Hesquiat Lake dock. 1 All times are Pacific Daylight Time (Coordinated Universal Time minus 7 hours). 2 SPOT Inc© is a GPS transmitter system that transmits the device’s position, usually once every 10 minutes. 3 Latitude is a GPS-based system that transmits position, ground speed, altitude, and heading at user- chosen intervals, in this case every 6 minutes. 2 | Transportation Safety Board of Canada Figure 1. Route of flight (Source: Google Earth, with TSB annotations) About 6 minutes later, C-GPVB crossed over the west shore of Hesquiat Peninsula while flying at about 400 feet asl. It continued east across the peninsula, arriving at the dock on Hesquiat Lake at about 1004. The weather there included rain, wind from the southeast, visibility about 2 ½ nm, and a ceiling of about 400 feet asl. The pilots of the other 2 Air Nootka aircraft inbound to Hesquiat Lake elected to stay over the shoreline of Hesquiat Peninsula for its entire periphery rather than cross the peninsula. The inbound pilots reported their locations and the weather along their route several times to C- GPVB’s pilot as they approached. At about 1023, the pilot of C-GPVB radioed the 2 inbound aircraft that he was off the lake and was going to take a look at crossing the peninsula westbound. C-GPVB flew westbound for about 2 minutes, climbing into cloud while staying just above tree-top level, until it struck a tree at about 800 feet asl. The pilots of the 2 inbound aircraft heard a brief “Mayday” on the radio, but were unable to contact C-GPVB afterward. C-GPVB came to rest in forest about 600 feet west of the initial tree strike. All 6 occupants survived the crash, but a short time later a post-crash fire ignited. Four passengers were able to exit the aircraft, but the pilot and 1 passenger remained in the aircraft, which was subsequently consumed by the fire. The 406 megahertz (MHz) emergency locator transmitter (ELT) transmitted a signal for a short period before it was destroyed by the fire. Aviation Investigation Report A13P0166 | 3 Figure 2. Arrival and departure from Hesquiat Lake (Source: Google Earth, with TSB annotations) Accident site The accident occurred about 3 nm west of Hesquiat Lake in mountainous terrain in the northern portion of Hesquiat Peninsula. The terrain from the southern tip of Hesquiat Peninsula to about 1 mile south of the accident site (about the southern 2/3 of the peninsula) is relatively level ground less than 200 feet asl. The tree that was hit was about 140 feet tall, significantly taller than the trees surrounding it. The aircraft struck the tree about 20 feet below its top and came to rest nose-down in forest about 600 feet further west. The tree is about 400 feet north (uphill) of a logging road running across the hillside in the same direction the aircraft was flying. It is not known if the pilot was using the road as a navigation aid. 4 | Transportation Safety Board of Canada Photo 1. Accident site The floats detached at final impact, but otherwise the aircraft remained largely intact until consumed in the post-crash fire (Photo 1). Aircraft General The aircraft was manufactured in 1956 and was operated by Air Nootka since April 2006. Records indicate that the aircraft was certified, equipped and maintained in accordance with existing regulations and approved procedures. The aircraft was equipped with a Garmin GPSMAP 296 global positioning system (GPS), and the pilot carried his own SPOT© Satellite Messenger tracker. The aircraft was not equipped for instrument flight rules (IFR) flight, nor was it required to be by regulation. It is not known if the pilot was using the GPS as a navigation aid on the accident flight leg. Flight tracking The aircraft was equipped with a Latitude flight tracking system. This system was normally only activated when Air Nootka was flying clients whose safety policy required a tracking system. It had been turned on partway through the leg of the flight from Louie Lagoon to Hesquiat Lake to ensure it would be working for an upcoming flight. However, it had been Aviation Investigation Report A13P0166 | 5 turned off when the aircraft landed at Hesquiat Lake and was not turned on again prior to the accident. Tracking system users choose the frequency of position reports transmitted by the equipment installed on the aircraft, in this case, every 6 minutes, and pay based on the number of position reports transmitted. Due primarily to the system’s purchase and operating costs, the other 2 company aircraft were not equipped with Latitude flight tracking systems. Pilot Records show that the pilot was certified and qualified for the flight in accordance with existing regulations. The pilot held an airline transport pilot licence and current medical. The pilot’s flight and duty times were not exceeded, and there were no indications of any health issues on the morning of the accident. The pilot had held a Group 1 instrument rating from January 1991 to February 1992, but did not have a valid instrument rating at the time of the accident, nor was one required for the type of flight, day visual flight rules (VFR), being conducted. The pilot had accumulated approximately 17 000 hours total flying time. The pilot had purchased Air Nootka in February 1994 and sold the company in May 2006. The pilot returned to fly temporarily for the company during the summer of 2007 and again for the summer of 2013. The pilot was very familiar with the aircraft as well as the local routes, terrain and weather. Weather The nearest official weather was recorded at the Estevan Lighthouse, British Columbia, about 6 nm south-southwest of the accident site, and 8 nm southwest of Hesquiat Lake. At 0940 the lighthouse keeper observed · overcast with 300 to 400-foot ceiling; · moderate rain and fog; · visibility 3 statute miles (sm); · wind out of the east at 15 knots, gusting to 26 knots; · sea state 4 feet with moderate low swell; · barometer 1013.6 hPa and rising (29.94 inches of mercury). The lighthouse weather at 1240 was nearly identical. Air Nootka pilots occasionally call Estevan Lighthouse for weather conditions in that area, but C-GPVB’s pilot did not speak to the lighthouse keeper on the day of the accident. It was reported that the weather at Hesquiat Lake when C-GPVB arrived included low cloud ceiling and reduced visibility in drizzle. When the other 2 Air Nootka aircraft arrived at Hesquiat Lake, about 20 minutes after C-GPVB departed, the ceiling was about 400 feet and visibility was about 2 ½ nm in rain with a gusty southeast wind. Weather conditions on the opposite (west) side of Hesquiat Peninsula were marginally better, with ceilings varying from 400 to 600 feet asl and visibility varying from 2 ½ to 4 nm in rain.